Poisson:
if no temporal information on the original data is available, the simplest procedure consists in choosing totally at random the timestamps of the temporal edges for each tie.
BTL-Poisson:
if the actual timelines of the
backbone ties are known, one can keep these actual timelines
and choose at random the timestamps of temporal edges only for the surrogate ties.
Stats:
we can instead assume that some information on the statistics of contact and inter-contact durations are known, as these properties have been shown to be extremely robust [1]}, [2]}
(see also Figure REF  in the Supplementary Material). They can moreover be approximately fitted to (truncated) power-law forms, meaning that the whole list of values is not needed, but only the parameters of the fit. We can then build a timeline of temporal edges for each tie using contact and inter-contact durations generated randomly from these fitted distributions.
BTL-Stats:
if the actual timelines of the backbone ties are known, we keep these actual timelines, and proceed as in the Stats case for the surrogate ties only.

